Toshiba 43VR9UM, Руководство по обслуживанию

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GENERAL ADJUSTMENTS
SPECIFIC INFORMATIONS
8-1-3 DATA TRANSMISSION FORMAT
Teletext data is transmitted on VBI TV line. Subject to availability, Lines 6 to 22 and 318 to 335 may be used to carry Teletext
data packets as shown in Fig. 8-1-3.
A Teletext data packet occupies one TV line. Each packet starts with a clock run-in and framing code
sequence for establishing bit and byte synchronization within the decoder. The framing code has a fixed timing relationship
to the line synchronization pulses of the video signal.
Signalling method: Binary non-return-to-zero (NRZ);
Bit Rate: 444 x nominal fHC(6.9375 Mbit/s
±
25 ppm)
Spectrun of data pulse: Skew symmetrical about 0.5 x bit rate, substantially zero by 5MHz
Video baseband signal level of element 1: 66
±
6 % of the difference between Black Level and Peak White Level
Video baseband signal level of element 0: Black Level
±
2 %0 V
Capacity of the whole data line: 360 bits organized as 45 bytes. In each byte, the bits are numbered 1 to 8
(LSB to MSB), and are normally transmitted LSB first.
Fig. 8-1-4
Fig. 8-1-3